One of my co workers decided to charge his drone at the office and found this out . Or more accurately the whole office did

Is there now a section of the employee policies that forbids charging drones in the office?

The manuals have always told people to charge outside, for this reason.

Not when the charger says "for home and office use only"

There's probably some weird clause in the usage guidelines saying you need to have the charger attended all times it is plugged in or something like that.

It's not just a clause. People will claim that this is the only safe way to charge them.

Personally, I think we need a cultural-architectural accommodation - we used to have coal chutes, milkman boxes, ice doors. For well-regulated but large batteries like an EV, a detached garage. For raw cells, a grill sitting on the driveway.

I have only had one "Spicy Pillow" from consumer devices (a phone-charger power bank), but with raw LIPOs in RC hobby gear it was an eventuality.

The DJI batteries and charger are very clever too. The batteries auto discharge to a safe level after 2 weeks on the shelf